CN113820555A

CN113820555A - Power equipment detection device based on Internet of things

Info

Publication number: CN113820555A
Application number: CN202111031585.XA
Authority: CN
Inventors: 郭小辉; 詹铭金
Original assignee: Nanjing Weiming Technology Co ltd
Current assignee: Nanjing Weiming Technology Co ltd
Priority date: 2021-09-03
Filing date: 2021-09-03
Publication date: 2021-12-21

Abstract

The invention discloses a power equipment detection device based on the Internet of things, and belongs to the technical field of power equipment detection. The utility model provides an electrical equipment detection device based on thing networking, includes the electrical equipment case, still includes: the placing frame is fixedly connected to the inner wall of the bottom of the power equipment box; the power equipment body is arranged on the placing frame; the temperature sensor and the thermal imager are respectively and fixedly connected to two sides of the inner wall of the power equipment box; according to the invention, the cooling liquid in the separation layer absorbs heat, so that the temperature in the power equipment box is reduced, and meanwhile, the heat outside the power equipment box is prevented from entering the power equipment box, so that the temperature in the power equipment box is effectively reduced, the power equipment body is prevented from working in a high-temperature environment for a long time, the circuit aging is accelerated to cause fire, and when the fire occurs, the dry powder storage tank is matched with the motor, the screw rod, the sliding block and the spray head, so that the purpose of quickly and accurately extinguishing the fire of the ignition point of the power equipment body is achieved.

Description

Power equipment detection device based on Internet of things

Technical Field

The invention relates to the technical field of power equipment detection, in particular to a power equipment detection device based on the Internet of things.

Background

The power equipment mainly comprises power generation equipment and power supply equipment, wherein the power generation equipment mainly comprises a power station boiler, a steam turbine, a gas turbine, a water turbine, a generator, a transformer and the like, and the power supply equipment mainly comprises power transmission lines, mutual inductors, contactors and the like with various voltage grades.

When present temperature check out test set was used for power equipment temperature to survey, owing to can not effectively reduce the temperature in the power equipment box to the temperature that leads to in the power equipment box is higher, causes power equipment often to break down, makes the circuit pencil accelerate ageing, has the potential safety hazard, causes the conflagration easily.

Disclosure of Invention

The invention aims to solve the problems that the temperature in a power equipment box cannot be effectively reduced, so that the temperature in the power equipment box is high, the power equipment often breaks down, a circuit wire harness is accelerated to age, potential safety hazards exist, and a fire disaster is easily caused in the prior art, and the power equipment detection device based on the Internet of things is provided.

In order to achieve the purpose, the invention adopts the following technical scheme:

the utility model provides an electrical equipment detection device based on thing networking, includes the electrical equipment case, still includes: the placing frame is fixedly connected to the inner wall of the bottom of the power equipment box; the power equipment body is arranged on the placing frame; the temperature sensor and the thermal imager are respectively and fixedly connected to two sides of the inner wall of the power equipment box; the supporting plate is fixedly connected to the inner wall of the power equipment box; the dry powder storage tank and the control module are fixedly connected to the supporting plate; the spray head is connected to the bottom of the supporting plate in a sliding mode, the spray head is communicated with the dry powder storage tank through a second guide pipe, an electromagnetic valve is mounted on the second guide pipe, and a driving part for driving the spray head to move is arranged at the bottom of the supporting plate; and the interlayer is arranged in the electrical equipment box.

In order to drive the spray head to move left and right in the power equipment box, preferably, the driving part comprises a motor installed on a supporting plate, the output end of the motor is fixedly connected with a lead screw, a sliding block is in threaded connection with the lead screw, and the spray head is fixedly connected to the sliding block.

In order to crush the dry powder stacked together, preferably, a second rotating shaft is rotatably connected in the dry powder storage tank, and a crushing rod is fixedly connected to the outer wall of the second rotating shaft.

In order to increase the pressure of the dry powder storage tank, the second rotating shaft is fixedly connected with a crankshaft, the supporting plate is fixedly connected with a piston assembly and a motor respectively, the piston assembly is connected with the crankshaft in a rotating mode, the piston assembly is connected with a third guide pipe, the piston assembly is communicated with the dry powder storage tank through the fourth guide pipe, and the output end of the motor is connected with the second rotating shaft through a belt.

In order to automatically control the opening or closing of the second conduit, preferably, an overflow valve is installed on the second conduit.

In order to dissipate heat of the cooling liquid, preferably, a U-shaped pipe is arranged in the interlayer, the side wall of the electrical equipment box is connected with a refrigerator, the output end of the refrigerator is connected with the air inlet end of the U-shaped pipe, and the output end of the U-shaped pipe is communicated with the outer wall of the electrical equipment box.

In order to provide protection for the refrigerator, further, the electrical equipment box lateral wall fixedly connected with protective housing, refrigerator fixed connection is on the protective housing, it has the filter screen to peg graft on the protective housing.

In order to improve the radiating effect to the power equipment body, further, the air inlet has been seted up to power equipment bottom of the case portion, the rack bottom is rotated and is connected with pivot one, fixedly connected with flabellum, impeller on the pivot one respectively, the air inlet is linked together through pipe one with the U-shaped pipe output, it has the active carbon filter screen to peg graft on the air inlet.

In order to discharge the cooling liquid in the interlayer, preferably, a conduit five is connected to the side wall of the electrical equipment box, the conduit five penetrates through the electrical equipment box and is communicated with the interlayer, and a valve switch two is mounted on the conduit five.

An electric power equipment detection method based on the Internet of things comprises the electric power equipment detection device based on the Internet of things as described in the right, and comprises the following steps: monitoring the temperature in the power equipment box through a temperature sensor and a thermal imager, and uploading signals obtained through monitoring to a server;

the server judges whether the power equipment box has a fire or not according to whether the highest heat limit is exceeded or not in the power equipment box;

when the heat exceeds a threshold value, the control module controls the electromagnetic valve to open to spray the dry powder in the dry powder storage tank; when the heat in the electrical equipment box exceeds a threshold value, a refrigerator outside the electrical equipment box cools the cooling liquid in the interlayer.

Compared with the prior art, the invention provides a power equipment detection device based on the Internet of things, which has the following beneficial effects: 1. this power equipment detection device based on thing networking absorbs the heat through the intraformational coolant liquid of separation for the temperature reduction in the power equipment box, and the external heat of separation power equipment box enters into the power equipment box simultaneously, thereby effectively reduces the temperature in the power equipment box, has improved the safe in utilization of power equipment body and circuit, avoids being in under the high temperature environment for a long time, accelerates the ageing conflagration that causes of circuit.

2. This power equipment detection device based on thing networking rotates through the motor drive lead screw, and the lead screw drives the slider and removes, and then carries out position control to the shower nozzle to make the shower nozzle remove directly over the ignition, open the solenoid valve simultaneously, because the atmospheric pressure in the dry powder storage tank is greater than the numerical value that the overflow valve set for, and then spout in making the dry powder in the dry powder storage tank carry the shower nozzle through pipe two, thereby reach and play quick accuracy to put out a fire to the power equipment body ignition.

3. This power equipment detection device based on thing networking, the motor passes through two rotations of belt drive pivot, two drive bent axles of pivot rotate, the pivot drives the motion of piston assembly, and then make bent axle 9 pass through the piston rod and drive piston plate reciprocating sliding in the piston cylinder, at this moment, the outside air passes through in the pipe three carries the piston cylinder, then carry in the dry powder holding vessel through four discharges of pipe, carry the pressure boost for the dry powder holding vessel, thereby the better blowout of the dry powder of being convenient for carries out the work of putting out a fire.

The device has the advantages that the temperature in the power equipment box is reduced by absorbing heat through cooling liquid in the interlayer, meanwhile, the heat outside the power equipment box is prevented from entering the power equipment box, so that the temperature in the power equipment box is effectively reduced, the power equipment body is prevented from working in a high-temperature environment for a long time, the circuit aging is accelerated to cause fire, and when the fire occurs, the dry powder storage tank is matched with the motor, the screw rod, the sliding block and the spray head, so that the purpose of quickly and accurately extinguishing the fire of the fire point of the power equipment body is achieved.

Drawings

Fig. 1 is a first schematic structural diagram of an electric power equipment detection device based on the internet of things, provided by the invention;

fig. 2 is a schematic diagram of an internal structure of an electric power equipment detection device based on the internet of things according to the present invention;

fig. 3 is a schematic partial structural diagram of a power equipment detection device based on the internet of things according to the first embodiment of the invention;

fig. 4 is a schematic partial structural diagram of a power equipment detection device based on the internet of things according to the present invention;

fig. 5 is an enlarged view of a portion a in fig. 3 of the power equipment detection device based on the internet of things according to the present invention;

fig. 6 is an enlarged view of a part B in fig. 4 of the power equipment detection device based on the internet of things according to the present invention;

fig. 7 is a schematic structural diagram of a power equipment detection device based on the internet of things according to the present invention.

In the figure: 1. an electrical equipment box; 101. an interlayer; 102. a hinge; 103. a side door; 104. heat dissipation holes; 2. a power equipment body; 201. placing a rack; 202. air holes are formed; 3. a temperature sensor; 301. a control module; 4. a protective shell; 401. a filter screen; 5. a refrigerator; 501. a U-shaped tube; 502. a first conduit; 503. a first rotating shaft; 504. a fan blade; 505. an impeller; 506. an activated carbon filter screen; 6. a thermal imager; 7. a dry powder storage tank; 701. a support plate; 702. a second conduit; 703. an electromagnetic valve; 704. an overflow valve; 705. a second rotating shaft; 706. a breaking bar; 8. a motor; 801. a screw rod; 802. a belt; 803. a slider; 804. a spray head; 9. a crankshaft; 901. a piston assembly; 902. a third conduit; 903. a fourth conduit; 10. a fifth conduit; 1001. and (6) opening and closing a valve.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

Example 1:

referring to fig. 1-7, an electric power equipment detection device based on thing networking includes electric power equipment box 1, still includes: the placing frame 201 is fixedly connected to the inner wall of the bottom of the power equipment box 1; the power equipment body 2 is installed on the placing frame 201; the temperature sensor 3 and the thermal imager 6 are respectively and fixedly connected to two sides of the inner wall of the power equipment box 1; the supporting plate 701 is fixedly connected to the inner wall of the power equipment box 1; the dry powder storage tank 7 and the control module 301 are fixedly connected to the support plate 701; the spray head 804 is connected to the bottom of the support plate 701 in a sliding manner, wherein the spray head 804 is communicated with the dry powder storage tank 7 through a second guide pipe 702, the second guide pipe 702 is provided with an electromagnetic valve 703, and the bottom of the support plate 701 is provided with a driving part for driving the spray head 804 to move; and the interlayer 101 is arranged in the electrical equipment box 1.

The driving part comprises a motor 8 arranged on the supporting plate 701, the output end of the motor 8 is fixedly connected with a screw rod 801, a sliding block 803 is connected to the screw rod 801 in a threaded mode, and the spray head 804 is fixedly connected to the sliding block 803.

And a relief valve 704 is arranged on the second conduit 702.

Firstly, cooling liquid is poured into the interlayer 101 through the filling port, then the sealing plug is covered, and the cooling liquid is called anti-freezing cooling liquid completely, namely the cooling liquid with an anti-freezing function, so that the heat insulation and heat dissipation effects on the power equipment box 1 can be prevented from being influenced by freezing of the cooling liquid in cold seasons;

when the power equipment body 2 works, the power equipment body 2 generates heat, so that the temperature in the power equipment box 1 rises, at the moment, the cooling liquid in the interlayer 101 absorbs the heat, the temperature in the power equipment box 1 is reduced, and meanwhile, the heat outside the power equipment box 1 is prevented from entering the power equipment box 1, so that the temperature in the power equipment box 1 is effectively reduced, the use safety of equipment and circuits in a cabinet body is improved, the power equipment body 2 is prevented from working in a high-temperature environment for a long time, and the circuit aging is accelerated to cause a fire;

meanwhile, the thermal imager 6 can monitor the temperature of the power equipment body 2, and the signals obtained by monitoring are uploaded to the server, the server judges whether the fire disaster happens to the power equipment box 1 when the temperature in the power equipment box 1 exceeds the maximum heat limit, when the temperature in the electrical equipment box 1 is too high to cause fire, at this time, the worker can send an instruction to the control module 301 through the remote control terminal, start the motor 8, the motor 8 drives the screw rod 801 to rotate, the screw rod 801 drives the slide block 803 to move, the position of the sprinkler head 804 is adjusted so that the sprinkler head 804 moves right above the ignition point, and at the same time, the solenoid valve 703 is opened, because the air pressure in the dry powder storage tank 7 is greater than the set value of the overflow valve 704, the dry powder in the dry powder storage tank 7 is conveyed into the spray head 804 through the second conduit 702 to be sprayed out, and therefore the purpose of quickly and accurately extinguishing the fire of the power equipment body 2 is achieved.

Example 2:

referring to fig. 3 and 5, an electric power equipment detection device based on the internet of things is substantially the same as that in embodiment 1, and further, a second rotating shaft 705 is rotatably connected in the dry powder storage tank 7, and a crushing rod 706 is fixedly connected to the outer wall of the second rotating shaft 705.

The second rotating shaft 705 is fixedly connected with a crankshaft 9, the supporting plate 701 is respectively and fixedly connected with a piston assembly 901 and a motor 8, the piston assembly 901 is rotatably connected with the crankshaft 9, the piston assembly 901 is connected with a third guide pipe 902, the piston assembly 901 is communicated with the dry powder storage tank 7 through a fourth guide pipe 903, and the output end of the motor 8 is connected with the second rotating shaft 705 through a belt 802.

When the motor 8 drives the screw rod 801 to rotate, the motor 8 drives the second rotating shaft 705 to rotate through the belt 802, the second rotating shaft 705 drives the crushing rod 706 to rotate, and further crushing and loosening the dry powder stacked together, so as to facilitate better spraying of the dry powder, meanwhile, the second rotating shaft 705 drives the crankshaft 9 to rotate, the crankshaft 9 drives the piston assembly 901 to move, because the piston assembly 901 comprises a piston cylinder, a piston plate connected in the piston cylinder in a sliding manner, and a piston rod rotationally connected on the piston plate, the piston assembly 901 is rotationally connected with the crankshaft 9, that is, one end of the piston rod far away from the piston plate is sleeved on the crankshaft 9, and further the crankshaft 9 drives the piston plate to slide in the piston cylinder in a reciprocating manner through the piston rod, at this time, outside air is conveyed into the piston cylinder through the third conduit 902, and then discharged and conveyed into the dry powder storage tank 7 through the fourth conduit 903, so as to pressurize the dry powder storage tank 7, thereby being convenient for the better blowout of the dry powder to carry out the fire extinguishing work.

Example 3:

referring to fig. 2 and 6, an electric power equipment detection device based on the internet of things is basically the same as that in embodiment 1, further, a U-shaped pipe 501 is arranged in the interlayer 101, a refrigerator 5 is connected to a side wall of the electric power equipment box 1, an output end of the refrigerator 5 is connected with an air inlet end of the U-shaped pipe 501, and an output end of the U-shaped pipe 501 is communicated with an outer wall of the electric power equipment box 1.

The air inlet has been seted up to electrical equipment box 1 bottom, and rack 201 bottom is rotated and is connected with pivot 503, fixedly connected with flabellum 504, impeller 505 on the pivot 503 respectively, and the air inlet is linked together through pipe 502 with the 501 output end of U-shaped pipe, pegs graft on the air inlet and has activated carbon filter 506.

When the temperature sensor 3 with higher temperature inside and outside the electrical equipment box 1 gives an alarm, the refrigerator 5 is started, the refrigerator 5 adsorbs outside air to refrigerate to generate cold air with lower temperature, at the moment, the cold air is conveyed into the U-shaped pipe 501, the U-shaped pipe 501 is installed in the interlayer 101, so that the U-shaped pipe 501 exchanges heat with cooling liquid absorbing heat through the cold air with lower temperature, the temperature of the cooling liquid in the interlayer 101 is reduced, meanwhile, the gas after heat exchange is discharged through the U-shaped pipe 501 and the first guide pipe 502, at the moment, the gas drives the first rotating shaft 503 to rotate through the impeller 505, the first rotating shaft 503 drives the fan blades 504 to rotate, and then the outside air is blown into the electrical equipment box 1 through the air inlet and the air vent 202, so that the heat dissipation effect on the electrical equipment box 1 is improved;

be equipped with active carbon filter screen 506 on through the air inlet, when gaseous through active carbon filter screen 506, because there are developed void structure and abundant micropore tissue inside the active carbon, these micropore tissues have powerful adsorption affinity field, when gaseous and active carbon contact, the powerful adsorption affinity field of active carbon micropore, can adsorb the particulate matter in the air in the micropore, and then reach the effect of purifying the gas, thereby avoid in external dust gets into power equipment box 1, influence the work of power equipment body 2.

Example 4:

referring to fig. 1, 2 and 4, an electrical equipment detection device based on the internet of things is basically the same as that in embodiment 1, further, a protective shell 4 is fixedly connected to a side wall of an electrical equipment box 1, a refrigerator 5 is fixedly connected to the protective shell 4, and a filter screen 401 is inserted into the protective shell 4; through installing refrigerator 5 in protecting crust 4, and then can provide the guard action to refrigerator 5, when avoiding colliding with, cause the damage, but refrigerator 5 is at the during operation simultaneously, but through the filter screen 401 on protecting crust 4 separation foreign matter, prevent that refrigerator 5 from at the during operation, adsorbing the foreign matter, influence refrigerator 5's normal work, because filter screen 401 is pegged graft on protecting crust 4 to be convenient for dismantle the clearance to it.

Example 5:

referring to fig. 2, 3 and 4, an electrical equipment detection device based on the internet of things is basically the same as that in embodiment 1, further, a fifth conduit 10 is connected to a side wall of an electrical equipment box 1, the fifth conduit 10 penetrates through the electrical equipment box 1 and is communicated with an interlayer 101, and a second valve switch 1001 is installed on the fifth conduit 10; the valve switch 1001 is opened, the five guide pipes 10 are in an open state at the moment, the cooling liquid in the interlayer 101 is discharged through the five guide pipes 10, so that the cooling liquid in the interlayer 101 is convenient to replace, meanwhile, the cooling liquid is often subjected to heat exchange with heat in the electrical equipment box 1, so that the cooling liquid in the interlayer 101 is less in evaporation, at the moment, the filling opening is formed in the top of the electrical equipment box 1, the filling opening interlayer 101 is communicated, and therefore the cooling liquid is convenient to supplement into the interlayer 101.

Example 6:

referring to fig. 1 and 7, an electric power equipment detection device based on the internet of things is basically the same as that in embodiment 1, further, a hinge 102 is fixedly connected to a side wall of an electric power equipment box 1, a side door 103 is fixedly connected to one end, away from the electric power equipment box 1, of the hinge 102, and heat dissipation holes 104 are formed in the side door 103; when needs maintain or maintain power equipment body 2, through fixedly connected with handle on the side door 103, open side door 103 through the handle this moment, and then reach the testing personnel of being convenient for and maintain or maintain power equipment body 2, because seted up multiunit louvre 104 on the side door 103, and then play ventilation cooling's effect to power equipment box 1.

Example 7:

an electric power equipment detection method based on the Internet of things, comprising the electric power equipment detection device based on the Internet of things as claimed in any one of claims 1 to 9, and comprising the following steps: firstly, monitoring the temperature in the power equipment box 1 through a temperature sensor 3 and a thermal imager 6, and uploading signals obtained through monitoring to a server;

the server judges whether the power equipment box 1 is in fire or not according to whether the highest heat limit in the power equipment box 1 is exceeded or not;

when the heat exceeds the threshold value, the control module 301 controls the electromagnetic valve 703 to open to spray the dry powder in the dry powder storage tank 7; the method is characterized in that when the heat in the electrical equipment box 1 exceeds a threshold value, the refrigerator 5 outside the electrical equipment box 1 refrigerates the cooling liquid in the interlayer 101.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims

1. The utility model provides an electrical equipment detection device based on thing networking, includes electrical equipment box (1), its characterized in that still includes:

the placing rack (201) is fixedly connected to the inner wall of the bottom of the power equipment box (1);

the power equipment body (2) is installed on the placing frame (201);

the temperature sensor (3) and the thermal imager (6) are respectively and fixedly connected to two sides of the inner wall of the power equipment box (1);

the supporting plate (701) is fixedly connected to the inner wall of the power equipment box (1);

the dry powder storage tank (7) and the control module (301) are fixedly connected to the supporting plate (701);

a spray head (804) which is connected to the bottom of the supporting plate (701) in a sliding way,

the spray head (804) is communicated with the dry powder storage tank (7) through a second guide pipe (702), the second guide pipe (702) is provided with an electromagnetic valve (703), and the bottom of the support plate (701) is provided with a driving part for driving the spray head (804) to move;

the interlayer (101) is arranged in the power equipment box (1).

2. The power equipment detection device based on the Internet of things of claim 1, wherein the driving portion comprises a motor (8) installed on a support plate (701), a lead screw (801) is fixedly connected to an output end of the motor (8), a sliding block (803) is connected to the lead screw (801) in a threaded mode, and the spray head (804) is fixedly connected to the sliding block (803).

3. The power equipment detection device based on the Internet of things of claim 1, wherein a second rotating shaft (705) is rotatably connected in the dry powder storage tank (7), and a crushing rod (706) is fixedly connected to the outer wall of the second rotating shaft (705).

4. The power equipment detection device based on the Internet of things of claim 3, wherein a crankshaft (9) is fixedly connected to the second rotating shaft (705), a piston assembly (901) and a motor (8) are respectively and fixedly connected to the supporting plate (701), the piston assembly (901) is rotatably connected with the crankshaft (9), a third guide pipe (902) is connected to the piston assembly (901), the piston assembly (901) is communicated with the dry powder storage tank (7) through a fourth guide pipe (903), and an output end of the motor (8) is connected with the second rotating shaft (705) through a belt (802).

5. The power equipment detection device based on the Internet of things of claim 1, wherein a relief valve (704) is mounted on the second conduit (702).

6. The power equipment detection device based on the Internet of things of claim 1, wherein a U-shaped pipe (501) is arranged in the interlayer (101), a refrigerator (5) is connected to the side wall of the power equipment box (1), the output end of the refrigerator (5) is connected with the air inlet end of the U-shaped pipe (501), and the output end of the U-shaped pipe (501) is communicated with the outer wall of the power equipment box (1).

7. The power equipment detection device based on the Internet of things of claim 6, wherein a protective shell (4) is fixedly connected to the side wall of the power equipment box (1), the refrigerator (5) is fixedly connected to the protective shell (4), and a filter screen (401) is inserted into the protective shell (4).

8. The power equipment detection device based on the Internet of things of claim 6, wherein an air inlet is formed in the bottom of the power equipment box (1), a first rotating shaft (503) is rotatably connected to the bottom of the placing frame (201), fan blades (504) and an impeller (505) are fixedly connected to the first rotating shaft (503) respectively, the air inlet is communicated with the output end of a U-shaped pipe (501) through a first guide pipe (502), and an activated carbon filter screen (506) is inserted into the air inlet.

9. The power equipment detection device based on the Internet of things of claim 1, wherein a fifth conduit (10) is connected to the side wall of the power equipment box (1), the fifth conduit (10) penetrates through the power equipment box (1) and is communicated with the interlayer (101), and a second valve switch (1001) is installed on the fifth conduit (10).

10. An electric power equipment detection method based on the Internet of things, comprising the electric power equipment detection device based on the Internet of things as claimed in any one of claims 1 to 9, and comprising the following steps: firstly, monitoring the temperature in the power equipment box (1) through a temperature sensor (3) and a thermal imager (6), and uploading signals obtained through monitoring to a server;

the server judges whether the power equipment box (1) has a fire or not according to whether the highest heat limit in the power equipment box (1) is exceeded or not;

when the heat exceeds the threshold value, the control module (301) controls the electromagnetic valve (703) to open to spray the dry powder in the dry powder storage tank (7); the method is characterized in that when the heat in the electrical equipment box (1) exceeds a threshold value, a refrigerator (5) outside the electrical equipment box (1) refrigerates the cooling liquid in the interlayer (101).